Apparatus for cleaning rubber.



No. salma. Patented Feb. s, |900.

a. www.

APPARATUS FUR CLEANING RUBER.

(Application led Apr. 1, 1899.)

(No Model.)

Ni'rnn .i STATES ltOlilClt'l UOWEN, OF CAMBRIDGE, MASSACHUSETTS.

SPECIFICATION forming part of Letters Patent No. 642,813, dated February 6, 1900.

Application iiled April 1, 1899. Serial No. 711,338. (No model.)

Be itkn own thatLROlERT COWEN, of Cambridge, county of Middlesex, State of Massachusetts, have invented an Improvement in -Apparatus for Cleaning Rubber, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing lik parts.

As is well known, rubber, whether it be the raw material or shoddy, dsc., which it is desired to work over again is usually more or less Iilled with foreign substances, such as bark, dirt, pieces of wood, stones, &c., in the case of the raw rubber, and nails, pieces of buckles, straps, cloth, and various other foreign substances in the case of shoddy, the. lleretofore the rubber has been cleansed of these foreign materials in Various Ways, the details of which it is unnecessary to set forth herein fu rthcr than to say that sometimes the rubber mass has been ground and dried and subjected to a blower which would separate the parts by gravity, and the metallic parts have been removed by being passed in front f of magnets, while also the fibrous foreign matter has been removed by being eaten away by sulfuric acid. All the methods mentioned have, however, more or less objectionable features and are also tedious and expensive, and accordingly I have invented the hereindescribed apparatus, which accomplishes the desired object quickly and thoroughly and does it in a simple manner and at slight expense.

Stated in general terms, my invention consists in means for reducing the rubber (whether in the form of raw or shoddy rubber or otherwise) to a plastic or partiallyfluid condition and then straining it, thereby separating the foreign substances (nails, strings, bits of leather, bark, the.) mechanically without in any wisedeteriorating or damaging the rubber. p

My invention will be more fully apprehended from the following detailed description thereof, reference being had to the accompanying drawings, in which I have illustrated a preferred embodiment of the meehanism employed, andthe invention will be more particularly defined in the appended claims.

. In thefdrawings,Figlue 1 is a central vertical longitudinal section of an apparatus for carrying out my invention; Fig. 2 is a transverse section taken on the line 2 2, Fig. 1. Figs. 3 and 4 are enlarged views, in front elevation and cross-section, of a fragment of the strainer-plate, showing one of the strainerdisks in place. Fig. 5 is a rear elevation of the outer strainer. Figs. 6 and 7 are views similar to Figs. 3 and i, showing one of the strainer-disks of the outer strainer considerably enlarged.

In carrying out my invention I make the rubber which is to be strained plastic or sufficiently fluid to flow under pressure, and for this purpose I preferably employ heat, inasmuch as this is the most convenient and readily-used means for accomplishing my purpose.

Referring to Fig. 1, it will be seen that I 'have shown a machine having some of the general characteristics-of an ordinary tube machine, the machine shown having a spirally-uted conveyer a within a jacket a', said jacket being provided with internal chambers a2 c3 for the free circulation of steam or hot water entering at the pipes a4 and passing out through pipes a, said conveyer being journaled at its rear end in the box a and provided with any suitable driving mechanism, a gear-wheel a7 being herein shown for convenience. y

The rubber is fed into the machine through a hopper as, the rubber being supplied in chunks or masses in any form-in. which the rubber or shoddy may reach this point in its manufacture in passing through the mill, and as it is caught by the rotating conveyer a, turningin the direction of the arrow, Fig. 1, it is forced .forward under considerable pressure, coming into contact with the heated walls of the chamber or surrounding jacket, so that by the time it reaches the farther end of the machine it is plastic, like d ough, just enough not to be inconveniently sticky.

At the forward end of the machine I provide one or more straine'rs b b', these strainers being herein shown as of special form, although it will be vunderstood that my invention comprises any kind of strainer having suliiciently small meshes to filter out the nails and foreign matter, which heretofore have been so expensively and tedious] y removed by the processes before alluded to.

Referring to the more detailed iguresof the drawings, it will be seen that I provide a plate (shown in Fig. 2 as an oblong plate b2) having a plurality of sets of holes b3, one of these holes being shown in enlarged detail in Fig. 4, where it will be seen that it has an annular shoulder b4. On this shoulder is supported a strainer-disk bi', and while I employ the term disk as a convenient descriptive term I wish it understood that I am not limited thereby in any way t0 shape orV size nor am I limited to any of the details herein described, inasmuch as myinventionincludes, broadly, theprovision of any plate or other means for supporting or containing the required reticulated surface through which the rubber may be forced in order to strain it. The disk or diaphragm 1151's preferably made from rigid steelbo'red transversely with a multitude of small strainer-holes 7L, placed as closely together and in such:arran gement as may be desired for the purposes in View.

One reason I employ the form of apparatus just described is because in order to force the rubber through the fine apertures h enormous pressure must be exerted, and it is mechanically impracticable to make a properlyapertured diaphragm or strainer of a large size capable of withstanding this pressure. Therefore I provide a plate b2 of sufficient thickness to withstand the pressure of the main body of the rubber being forced along by the conveyer, and in this plate I provide small holes having shoulders which give firm support to small and thin diaphragms, which constitute the active strainers or strainer-surfaces.

The circular' or disk-like form employed gives the greatest strength, and I locate the ledges b at a considerable depth within the plates in order to provide pockets h6 on the innersides ofthe strainer-disks, in which the foreign mattermay accumulate as it is strained out from the mass of rubber being forced through the strainer.

Preferablya series of strainers are provided for the best work, each successive strainer having finer meshes than the preceding one, two of these being herein shown as sutiicient for purposes of illustration, these being illustrated in approximately their actual size in Figs. 3 and 6, the former showing the coarse strainer and the latter showing the fine strainer.

Theplate b is herein shown as mounted to slide transversely in ways a7 provided at the opposite sides of the machine, so that as one set of pockets D gets lled with detritus and waste the strainer-plate can sim ply be shoved endwise to the right, as shown in Fig. 2, thereby'carrying the choked and filled strainers out of the machine and replacing them with the set of clean strainers at the other end of the plate. Thus the flow of rubber may be practically uninterrupted, and meanwhile the foreign matter accumulated by the l rst set of strainers may be removed and the strainers cleaned, broken and damaged ones replaced, dsc. Then when the second set of strainers has become choked with foreign matter the plate is moved to the lett, bringing again the renewed and clean rst set of strainers into active operation and carrying out the second set to be cleaned.

4The cleaning is effected by simply pushing the strainer-disks out from their recesses to the left, Figs. 4 and 7, thereby removing the accumulations from the pockets, and then the disks themselves maybe cleaned in any convenient` manner. Y

As the plate b2 is slid longitudinally ono way or the other the body of rubber within the cylinder of the machine is sheared oI'f by the edge of the cylinder, so that simply such portions of the rubber and accumulations as are contained in the pockets of the strainer are carried out by the plate.

The plate b is herein shown as removable endwise of the machine, being held in by a perforated back piece or block b, shown as screw-threaded at L10, although it may be held in by any other means, lugs Z112 being provided thereon to receive a bar or other means for rcmoving it from the machine.

In the case of shoddy containing considerable brous material 'I first macerate the shoddy and soak it in a solution of sulfuric acid to eat away the threads and finer portions of organic material, and then I feed the mass to the machine and force it under pressure and in a plastic condition, as alreadyexplained, through the strainer.

I regard it as broadly new to clarify rubber by forcing it in a plastic condition, as described, through mechanical strainers, and accordingly I do not intend to limit my invention to any details otherwise than as expressed in the claims, and while I have confined my description for convenience to rubber I wish it understood that I do not by this term mean to limit my invention to rubber, technically so called, but intend to include thereby any similar or analogous substance requiring substantially similar cleaning.

Having fully described my invention, what I claim, and desire to secure by Letters Patent, is-

1. An apparatus for cleaning rubber, comprising a foraminous strainer, a conveyer to feed the rubber thereto under pressure, and a heated jacket or cylinder inclosing said conveyer for heating the rubber to a plastic condition, substantially as described.

2. In a machine for cleaning rubber, a strainer comprising a holdin g-plate of considerable depth and strength suitably apertured, the apertures having ledges, and foraminous strainer-diaphragms seated on said ledges,and means for feeding the rubber thereto, substantially as described.`

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IIO

3. A strainer of the kind described, consisting of a strong metal holder havinga hole through it, said hole liaving asmall diameter on the back side and a larger diameter on tho front side of the plate, and an intermediate ledge, combined with a removable, thin, foraminous diaphragm resting on said ledge, substantial] y as described.

4. A strainer of the kind described, consisting of a strong metal holder having a hole through it, said hole having a small diameter on the back side and a larger diameter on the front side of the plate, and an intermediate ledge, combined with a removable, thin,.fo raminous diaphragm resting ou said ledge, said holder affording a pocket or recess at the front of said diaphragm, substantially as described.

5. In a machine for cleaning rubber, a strainer, and means for feeding the rubber thereto under pressure, said strainer being movably mounted in the machine, and the walls of the machine having openings fitted to receive said strainer and through which the strainer may slide, substantially as de:

scribed.

6. In a machine for cleaning rubber, a strainer in the form of an oblong plate having a plurality of sets of apertures provided with foraminous diaphragms, said plate being mounted in a slidewayin the Wall of the Inachine and capable of being slid back and forth to bring one or the other of said sets of apertures into operative position, substantially as described.

7. In a machine for cleaning rubber, a plurality of strainers, one behind the other, said strainers having successively-hner strainerholes, and means to force the rubber through said strainers under pressure, substantially as described.

In testimony whereof I have signed my name to this specilication in the presence of two subscribing witnesses.

ROBERT COWEN.

Witnesses:

E. 1I. IIUXLEY, W. F.- ROBINSON.

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